I work in c# 2015 windows form
I have excel file 2007 name book 1 and sheet inside it name sheet 1
sheet 1 have two column
UserID
UserName
I need when insert new record from windows form c#
to check if the value of User Name found before show to client message tell him that Username exist before
UserID UserName
1 michel
2 marten
IF user enter in textbox value of marten then click button insert
give me message that this name exist before
using c# windows form
How to do that by c# if possible using oledb